Pump piston



Dec. 18, 1928,

w. c. GAGE PUMP PISTON Filed June 22, 1926 WC GAGE IN ENTOR ATTORNEY Patented nee. 13, 1928.

WAL'IEE'C. GAGE, or nonvoxn, MASSACHUSETTS, Assmnon mo woJs'THmGroN BUMP,

AND MAcnmERY oonrosa'r oiv, or NEW YORK, y- -Aconronarmnos v11:-

PUM? mason.

v Application fil ed.1une22, 192 .v Seria1.l to. 117,6 7'2.,

This invention relates to pistons and more particularly to pistons designed for *use in displacement pumps employed tor pumping hotl-iquid, such as hot petroleum or its prod u.e cts,-especially pumps used in 'oilrefining Operation such as crackin stills tor, producing ga solene. V l Y In, pumps commercially known as hot oil pumps considerable ditficulty, lossot time in operation with rednc ed, refinery vcapacity and consequent expense is enconntered'in that the wear o t'the piston andthe pump cylinder lining is very rapid so that on certain installa-v tions it has been necessary to replace pump 15. pistons every, few months, andv also dueto'the tactfthatthe snap rings stick andbecOme prtu iticallyv integral parts oi the piston, due to carbon or other ,accumulations, thereby destroyin'g their ettectiyen ess and making it 20111606883137 to cut them out ot tshe piston for replacement. 1

An object of the present invention is to provide a piston which will obviate the difficnlties above ennmerated and onewhich will materially reduce the expense of repairs in the-entire piston, when wear taltes pl'ace and reduces the efficiency of the piston.

The; invention comprehends substantially a piston of composite design comprising a pair ot piston elements which are held' togetherby the piston rod nut so as to permit the piston to be easily taken apart to clean out any foreign matter which may lodge under the snap rings and make them inoperative, and for replacing the wide faced centering ring used in the piston construction, which ring takes up the wear and permits replacement in case of wear, at a relatively small ex pense.

lVith these objects in view, the invention consists in various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a pump piston of the preferred form embodying the invention, and the features forming the invention will be specifically pointed out in the claims.

' In the drawings-- tion, of a displacement pump for pumping hot fluids, and illustrating the piston as used.

Figure 2 isa longitudinal section through the piston with the piston rod removed.

Figure 1 is a side elevation partly in sec-' Figure 3 isa C rQSs-section on the line 3-3 s R at s arr ng more 1IlgS, I pinnp, of, y approved constrhctiomsuch' as used forqthepuimping 0t hotliquids, preferl,1ot,p,e troleum oils, and this" pump strucn rticularly to the draw- F gn ifefl illustrates a displacement with the, necessary connections 0 I therebetwee term na ing this pis es 0f the 11 1. 1 mgor fluidgend A. U

The piston 1 Ciprqcates within the cylinder lining' 2m'ounted in. thelbore 3 oiithe cylinder-(4t; and itfis connected to the steam or Bowel end lby, thepiston rod: 5, A Suitable design comprising thetwopiston elements 10 and;- 11 which are, snbstantially, of the same ite and. hape. I

To make it unnecessary to replacethe enthat it will make it unnecessar to reolace tire jiston when wear takes olace durino the 01 mm o h tes ai fil ataee teet i r1ng'12 isprovided, and th s v centering ring '12 fits in annula esses 13 and 14 tormedln the elements 10 and 11 at; thleir inner facing gagement with the edges of the centering ring 12 by the, piston rod nut 16 which is threaded on the end of the piston rod 5 and clamps against the flat surface 17 on the piston element 11. The piston rod receiving bore 18 ot the piston element 10 is tapered as clearly shown in Figure 2 of the drawings to facilitate thewedging action and firm clamping of the piston elements 10 and 11, centering ring 12 and piston rod 5 in a compact unit The piston elements 10 and 11 are provided with annular recesses 19 and 20 and form grooves with the centering ring on one side.

which receive eccentric snap rings 21 which are relatively stiff and strongly expansive to holdthem against the inner surface of the cylinder lining 2. As the area of the ring in contact with the cylinder lining is large, the contact pressure per unit area is low enough for the wear of the cylinder lining jack bolt holes 24 are provided in the piston 7 element or follower 11 and these openings extend from the flat face 17 throughthe element or follower 11 to its inner surface. The element or follower 11 is a slightly loose tit on thepiston rod 5 so that by taking off the piston rod nut 16, which is castellated, eye bolts can be screwed into'the jack bolt openings 24, for use in pulling the element 11 oil the piston rod, or if the parts of the piston are carbonized together, the eye bolts may be screwed through the openings 24 and against the piston element 10 so that they act as jatiis to force the elements 10 and 11 apart.

Jack bolt holes 25 are also provided in the centering ring 12 to facilitate the separating of the centering ring from the element or head 10, and the ring is further provided with an annular groove or cut-out 26 in its inside face which makes it possible to get a pinch bar in at this point to force the centering ring 12 off the piston head or element, if required.

As clearly shown in Figure'2 of the drawings, the jaclrbolt holes 2% are covered with the piston rod nut 16 which will prevent any tendency of the openings to fill. with hot oil and then carbonize, and the openings 25 are closed by shoulder 14;, with the same result.

From the foregoing description taken in connection With the accompanying drawings,

it will be apparent that a piston construction has been provided which will make it unnecessary to replace the entire piston when Wear takes place in that the centering ring 12 maybe replaced at a small expense and Will then permit a piston considerably reduced in diameter to be successfully and effectively used.

It will be understood that the invention is not to be limited to the specific construction or arrangen'ient of parts shown but that these may be modified widely within the invention defined by the claims} lVhat is claimed is: V v 1. A pump piston of compositeconstruction comprising a pair of elements provided with annular recesses in their perimeters on their adjacent ends to form a groove, a centering ring in said'g'roove overlapping "thejoint between the elements, each of saidelements provided with an eccentric, annular groove adjacent the annular recesses therein, said grooves disposed whereby the shallowest portion of one groove will be opposed to the deepest portion of the other groove, and snap rings in said eccentric grooves.

' 2. A pump piston of composite construc V tion comprising a pair of elements provided with annular recesses in their perimeters on their adjacent ends to form a groove, a centering ring in said groove overlapping the joint between the elements,'each of said elements provided with an eccentric, annular groove adjacent the annular recesses therein, said grooves disposed whereby the shallovvest portion of one groove will be opposed to the deepest portion of the other groove, and snap rings in said eccentric grooves, said centering ring provided with an annular groove invits inner face spanning the joint between the elements.

In test mony whereof I affix my 's1g'nature.

WVALTER C. GAGE. 

